Bio-efficacy of some commercially available Neem Formulations on Diamondback Moth, Plutella xylostella (L.) on Cabbage

Two field experiments were conducted during the rabi seasons of 1998–99 and 1999–2000 at the Experimental Farm of Division of Entomology, IARI, New Delhi to study the effect of commercially available neem formulations, neemazal, neemgold and nimbecidine having 50000, 1500 and 300 ppm azadirachtin, respectively, against the diamondback moth, Plutella xylostalla on cabhage. The bioefficacy in a descending order was: neemazal > nimbacidine > neemgold. During 1998–99, the maximum population reduction over control was found after 7 days of application viz., 74.52, 70.17 and 55.68 per cent due to neemazal, nimbecidine and neemgold, respectively. A similar trend was found in 1999–2000. Thus, neemgold, respectively. A similar trend was found in 1999–2000. Thus, neemazal was most effective against the diamondback moth, P.xylostella.